Recently, I've been looking at web programming trends to try to see which way the industry is going. Over the past 2 or 3 years, there has been a shift away from the more traditional server-client web applications built using php, .net, ruby, java and such - where the server does all of the processing and spits out the resulting dumb html to the client. As server demands have increased, the scaling method of just upgrading the server to have faster processors or more memory becomes a limiting factor (vertical scaling). Instead, the more recent trend has been to make front end, in-browser code more intelligent and do more of the work, and the server more streamlined so that it does mainly optmised web services, spitting out raw JSON code in response to client requests.
The most popular front end frameworks are angularjs, ember.js, and backbone which have been developed to create Single Page Applications (SPA's). SPAs handle all the complex UI and business logic and only call back to the server when they need to update from central databases, eg hotel search results or auction listings.
Another trend is to make servers which are more flexible and agile. So data is consumed via RESTful web services, often using JSON instead of XML as this can more easily be used with noSQL databases like MongoDB, Cassandra or Redux. (the advantage of noSQL databases is that they allow for flexible data structures and can handle massive data sets using horizontal scaling or 'sharding' as its often referred to). Server technology like NodeJS or .net Core is very lightweight and only uses those modules which are required for the service so is very fast and can handle many thousands of requests per second.
The graph below, taken from Google Trends, shows that the most popular search is for AngularJS. It looks like Angular 2 has been gaining ground at the expense of angular 1 - Angular 2 is a completely rewritten framework and changes a lot from version 1. A newer framework, vue.js was developed by one of the founders of angular because he was not happy with the way that the project was heading. Vue.js shares a lot of similarity with angular 1 and is probably worth watching for the future, however the main winner in this battle looks to be angular 2. If trends continue in the same direction, angular 2 will be the most popular search phrase by the end of next year.
View current trends here
So Should I Learn Angular 2 then?